﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Security.Cryptography;

namespace Xiaov.SmartWeb.Infrastructure.ExtMethod
{
    /// <summary>
    /// 加密解密
    /// </summary>
    public static class DESEncrypt
        {
            #region ========加密========

            /// <summary>
            /// 加密
            /// </summary>
            /// <param name="Text"></param>
            /// <returns></returns>
            public static string Encrypt(this string Text)
            {
                return Encrypt(Text, "ppacom");
            }
            /// <summary> 
            /// 加密数据 
            /// </summary> 
            /// <param name="Text"></param> 
            /// <param name="sKey"></param> 
            /// <returns></returns> 
            public static string Encrypt(string Text, string sKey)
            {
                DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                byte[] inputByteArray;
                inputByteArray = Encoding.Default.GetBytes(Text);
                des.Key = ASCIIEncoding.ASCII.GetBytes(System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));
                des.IV = ASCIIEncoding.ASCII.GetBytes(System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));
                System.IO.MemoryStream ms = new System.IO.MemoryStream();
                CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);
                cs.Write(inputByteArray, 0, inputByteArray.Length);
                cs.FlushFinalBlock();
                StringBuilder ret = new StringBuilder();
                foreach (byte b in ms.ToArray())
                {
                    ret.AppendFormat("{0:X2}", b);
                }
                return ret.ToString();
            }

            #endregion

            #region ========解密========


            /// <summary>
            /// 解密
            /// </summary>
            /// <param name="Text"></param>
            /// <returns></returns>
            public static string Decrypt(this string Text)
            {
                return Decrypt(Text, "ppacom");
            }
            /// <summary> 
            /// 解密数据 
            /// </summary> 
            /// <param name="Text"></param> 
            /// <param name="sKey"></param> 
            /// <returns></returns> 
            public static string Decrypt(string Text, string sKey)
            {
                DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                int len;
                len = Text.Length / 2;
                byte[] inputByteArray = new byte[len];
                int x, i;
                for (x = 0; x < len; x++)
                {
                    i = Convert.ToInt32(Text.Substring(x * 2, 2), 16);
                    inputByteArray[x] = (byte)i;
                }
                des.Key = ASCIIEncoding.ASCII.GetBytes(System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));
                des.IV = ASCIIEncoding.ASCII.GetBytes(System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));
                System.IO.MemoryStream ms = new System.IO.MemoryStream();
                CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);
                cs.Write(inputByteArray, 0, inputByteArray.Length);
                cs.FlushFinalBlock();
                return Encoding.Default.GetString(ms.ToArray());
            }

            #endregion
        }
}
